1. Field of the Invention
This invention relates to a compact lance for the introduction of oxygen during a combustion process. The lance has a closer and a collet chuck, which allow a tuyere to be introduced into the handle in a manner which prevents twisting. An axial gasket is positioned to be placed in contact with the tuyere and is partly enclosed by a gasket sleeve. The gasket is compressible by the collet chuck between a shoulder, positioned adjacent an inner hole, and a sleeve which encloses the end of the tuyere.
2. Description of the Prior Art
Compact lances are used during oxidation processes, such as steelmaking processes, to connect partly consumable oxygen lances, or tuyeres, with a handle to insure that the oxygen lances, or tuyeres, are securely mounted during handling. Tuyere holders are generally disclosed in German Utility Model No. 19 39 317 and German Patent No. 23 27 595. Tuyere holders of the prior art include a handle which has a housing with an inner hole having shoulder-type stops for supporting and acting as a bearing for various insertable devices. The tuyere is inserted into an inner hole of the holder and into a closer and collet chuck. Once inserted into the holder in this manner, the tuyere is mounted in a sleeve, which has a slag holdback device. The slag holdback device may then be opened when the tuyere is mounted in the sleeve.
The holder comprises two exterior cover members which are connected to one another by cooperating screw-type threads. When the cover members are screwed together tight, the collet chuck becomes compressed so that it holds the inserted tuyere in place. Also, when the cover members are being screwed together, the collet chuck is moved toward the inserted end of the tuyere, thereby compressing a gasket, which is mounted in a gasket sleeve, against the tuyere. The gasket provides a gas-tight connection between the end of the tuyere and the end of the tuyere holder or handle.
Depending on the type of combustion process, either straight tuyeres or curved tuyeres are used. When using a curved tuyere, there is a danger that the collet chuck will rotate when the tuyere is rotated, thereby unintentionally loosening, and possibly disengaging, the tuyere from the handle. Even if the tuyere is only loosened, but not completely disengaged from the handle, it may be more difficult to reach the point where oxygen is to be applied with the curved end of the tube. German Utility Model No. 75 08 317 discloses a quick-action stop valve which can be activated by means of a control lever. However, even with this device, twisting of the collet chuck is not prevented.